Coating for nitrocellulose powder grains



Patented Get. 17, 1922;

' UNM'ED STATES TENI'EY L. DAVIS, OE SOHIERVILLE, MASSACHUSETTS.

COATING FOB- NITBOCELLULOSE POWDER GRAINS.

No Drawing. Original application filed April 16, 1921, Serial No. 162,028. Divided and this application filed April 25, 1922.

Serial No. 556,525.

(FILED urmna m ACT or Mason 3, 1883, 22 srar. I.., 625.

T all'whom-z't may ooqtcem:

Be it known that I, TENNEY L. DAVIS, a. citizen of the United States, and a resident of Somerville, county of Middlesex, and State of Massachusetts, have invented an Improvement in Coatings for Nitrocellulose Powder Grains, of which the following is a specification. The invention described herein may be used by the Government, or any of its oilicers or employees in-prosecution of work for the Government, or by any other person in the United States, without payment to me of any royalty thereon.

for nitrocellulose powder grains and this application is a division of my application for gelatinizing agents for nitrocellulose, filed April 16, 1921, Serial No. 462,028.

The main advantages of this invention reside in the fact that powders coated with the substances will be less hygroscopic than ordinary smokeless powder and will show in a greater degree the phenomenon of p-ro-' gressive burning, givlng higher velocity to' the projectile while producing lower gas pressures in the barrel of the gun. Whether these substances are incorporated throughout the mass of powder grain or are only amalgamatedwith the surface they will have the effect of rendering the powder cooler and slower. As these substances are not sensibly hygroscopic, their use in place of part or all of the usual alcohol-ether or acetone solvent, will reduce the tendency of the powder to take moisture. Their amount may be so regulated as to render the powderflashless.

For sometime it has been the practice to 40 incorporate with the nitrocellulose which is used in the manufacture of smokeless powder certain other nitrogenous substances, particularly substituted ureas and substituted urethanes which modify the nature of the The subject of this invention is a coating lidones.

resulting colloid. Certain of these stances act also as stabilizers, combining with the products of the spontaneous decomposition of the nitrocellulose and so lengthening the effective life of the powder. .These same substances are used also'for coating smokeless powder grains. When applied to powder by methods which are well known, these substances amalgamate with'the surface of the grain and modify its physical condition rendering the surface less pervious to moisture and slower burning than the surfaces of uncoated powder grains. Incorporated throughout the mass of powder grains, thesesubstances render the powder slower burning and cooler, and consequently reduce its erosive effect and, in certain cases, may even. produce flashlessness of. discharge.

I have discovered that certain nitrogen compounds of the type known as heterocyclic compoundsare eminently satisfactory for use in coating grains of nitrocellulose powder. Noteworthy among such substances are the substituted pyrazolones and pyrazo The formulas of the unsubstituted parent substances are given below:

t NH CHz-CO Pyrazolone My experiments indicate, for instance, that diphenylpyrazolone is the most efiicient substance for coating nitrocellulose powder grains and I also find that phenyldimethylpyrazolone which has been used extensively in medicines under the name of antipyrine is also an excellent material for this purpose.

I claim: w

1. A nitrocellulose smokeless powder, the

Pyrazolidone grains of which are coated with a nitrogen compound of the heterocyclic type. t

2. A nitrocellulose smokeless powder, the grains of which are coated with a pyrazolone derivative. TENNEY L. DAVIS. 

